The present invention generally relates to tape end detecting device in recording and/or reproducing apparatuses for miniature type tape cassettes, and more particularly to a tape end detecting device for detecting an end of a tape which is accommodated within a miniature type tape cassette, in a tape rewinding and fast-forwarding modes of a recording and/or reproducing apparatus which carries out recording and/or reproduction when loaded with the miniature type tape cassette.
As a device for detecting an end of a cassette tape which is drawn out from a cassette case and loaded unto a predetermined tape path in a recording and/or reproducing apparatus for recording and/or reproduction of a video signal, there was a device disclosed in a U.S. Pat. No. 4,091,426 entitled "DEVICE FOR DETECTING AN END OF A CASSETTE TAPE" in which the assignee is the same as that of the present application. A tape cassette employed in this tape end detecting device comprises a first reel having an opaque tape wound thereon, with one end of the tape connected to a transparent first leader which is fixed at its other end to the hub of the reel. A second reel receives the tape as it is wound. This tape is connected to one end of a second transparent leader which is fixed at its other end to the second reel hub. A cassette case containing the reels has first and second windows in at least one side wall, and a hole for receiving a light-emitting element at an intermediate position between the first and second windows. The tape end detecting device comprises a light-emitting element which is inserted into the hole in the above cassette case, and first and second light-receiving elements respectively disposed on opposite sides of the tape, relative to the first and second windows. The first light-receiving element receives the light passing through the first leader and the first window when the first leader assumes a position intercepting a light path connecting the light-emitting element and the first light-receiving element, to detect an end of the tape at the first reel. The second light-receiving element receives the light passing through the second leader and the second window when the second leader assumes a position intercepting a light path connecting th light-emitting element and the second light-receiving element, to detect an end of the tape at the second reel.
According to this known tape end detecting device, it is also possible to detect the end of the tape during tape rewinding and fast-forwarding modes of the recording and/or reproducing apparatus when the tape is accommodated within the cassette case, in a manner similar to the case where the tape is drawn out of the cassette case and loaded unto a predetermined tape path within the recording and/or reproducing apparatus for carrying out normal recording and reproduction.
On the other hand, a miniature type tape cassette was proposed in a U.S. patent application Ser. No. 322,766 filed Nov. 19, 1981 in which the assignee is the same as that of the present application. This proposed miniature type tape cassette has a volume which is reduced to approximately 7/8 that of the normal tape cassette which cooperates with the known tape end detecting device described heretofore, and such a miniature type tape cassette has been reduced to practice. The miniature type tape cassette has a considerably compact design, and in a cassette case of this miniature type tape cassette, there is no space to provide a hole which corresponds to the hole for receiving the light-emitting element in the cassette case of the normal tape cassette.
Accordingly, in a recording and/or reproducing apparatus designed exclusively for the above miniature type tape cassette, the tape end detecting device is designed to detect the end of the tape which is drawn out of the miniature type tape cassette and loaded into a predetermined tape path in the recording and/or reproducing apparatus. Specifically, in such a tape end detecting device, a light-emitting element and a light-receiving element are provided opposing each other across the predetermined tape path, at a position close to the miniature type tape cassette. Thus, the end of the tape is detected when the transparent leader reaches a position between the opposing light-emitting element and light-receiving element.
However, the load on the tape is large when the tape travels in the above predetermined tape path. For this reason, when the recording and reproduction is not carried out and the tape is simply moved at a high speed as in the tape rewinding and fast-forwarding modes of the recording and/or reproducing apparatus, the tape is unloaded from the predetermined tape path to be accommodated within the cassette case of the miniature type tape cassette before moving the tape at the high speed. Hence, in the recording and/or reproducing apparatus designed exclusively for the miniature type tape cassette, it was impossible to detect the end of the tape during the tape rewinding and fast-forwarding modes of the recording and/or reproducing apparatus.